When an injured person is alone or medical assistance is not immediately available, loss of blood is a major risk of death. The use of a tourniquet to stop blood loss from an injured arm or limb is well known. Without help and bleeding profusely, the injured victim must be able to apply a tourniquet to his or her own arm or limb using only one hand to have a chance at survival.
Tourniquets of the prior art comprise an elongated strap and a buckle and another component intended to increase circumferential pressure on the limb, such as a ratchet to windlass. The ratchet and windlass generate inward radial compression when the tourniquet is wrapped around the injured limb by using high levels of circumferential tension. As the pressure on the limb increases, the friction between the tourniquet and the limb also increases, causing the underlying soft tissue to move with the strap as it is drawn tighter. Soft tissues underlying the strap may be drawn into the buckle where the soft tissue may be pinched by the very highly localized pressure against it. Shearing forces may also endanger the soft tissue, increasing the probability of nerve damage and tearing. Friction between the strap and the limb may also create regions of low pressure where tension is not evenly distributed by the strap around the limb's circumference, and, as a result, arterial blood may not be completely staunched despite high tension on the strap.
In general, the application of uneven pressure around the limb may drive overall tourniquet pressures ever higher to stop arterial blood flow, while also increasing the probability of a range of injuries to nerves, muscles, and limbs.
Those engaged in activities where the risk of serious injury is heightened, including many recreational activities, such as hiking, rock climbing, and camping, will select the gear they take with them based on various criteria, including weight. Simply stated, if a tourniquet is too bulky or has an excessive weight, the potential user will not pack and carry a tourniquet. A small, lightweight tourniquet that can be easily packed and carried is more likely to be included as part of recreational gear.
Accordingly, there is a need for an easy to use, lightweight tourniquet that effectively restricts blood flow, and that ideally can be applied with one hand, without pinching, tearing, or otherwise damaging soft tissues.